Android 4.1 Jelly Bean CM10 Up for AT&T Galaxy S3 [How-To]
CyanogenMod team has arrived for A&T Galaxy S3 with CaynogenMod 10 (CM10) officially that based on latest Google mobile operating system version, the Android 4.1 Jelly Bean, just after Sprint Galaxy S3. Though the custom ROM is available officially but it’s still preview build and can’t be used for daily drive. Since this is early build, it has some bugs like your camera will preview turns green during animations, it also may crash. Sometime the audio dies, CM10 team will iron out these bugs soon but if you want to taste this AOSP ROM, be sure to follow below guide to install CyanogenMod 10 on your AT&T Samsung Galaxy S3.
Before installation, first do keep in mind that ClockworkMod recovery must be installed on your AT&T smartphone, don’t use any other recovery, you can follow this guide to install ClockworkMod, you also have option to get ClockworkMod with all-in-one toolkit. Make a backup of your device data such as SMS, internet setting, contacts music files etc because the below procedure may wipe data, you can sync your contacts with Gmail account and for messages use SMS apps, lastly use file expert app to backup apps.
DISCLAIMER: Please proceed the below guide at your own risk, Android Egis will not be held responsible if your device lost data or get damaged following this guide.
Step #1: Download the latest version of ROM from here [XDA LINK] and also download Google Apps to PC.
Step #2: Transfer the downloaded files to the internal SD card of device.
Step #3: Turn the device off and put it into recovery mode, to do it, simply reboot the device by holding down volume, home and power buttons.
Step #4: In recovery mode, create a nandroid backup of your current ROM, it’s important because if anything not work out that you expect from this ROM, you’ll be able to easily revert back to your current state. To create backup select “Backup and Restore”, and then select “Backup” again.
Step #5: Perform wipe, to do so, select the wipe data/factory reset, and confirm on the next screen.
Step #6: Select “Install Zip from SD Card” then “Choose Zip from SD Card” and locate the downloaded file that you’ve transferred in above step and confirm installation. Wait till installation complete.
Step #7: Repeat the step 6 and install Google Apps.
Step #8: Once the installation is completed, select “Go Back” after that select “Reboot System Now.”
That’s it, when you need to go back, simply put the phone in recovery mode and restore that backup that you taken in step 4. If you faced any issue, do comment below and I’ll help you. You can also visit the original thread link given in step 1.